Heavy rain from Typhoon Lionrock flooded towns across Japan's north and left at least 11 people dead, most of them elderly residents at a nursing home who could not escape rising floodwaters, officials said Wednesday.

The home in the town of Iwaizumi, which only had the ground floor, included people suffering from dementia who were in their 80s and 90s. Police discovered nine bodies there on Wednesday while checking another facility in the inundated neighborhood.

As floodwaters rapidly rose on Tuesday night, all 85 elderly residents and staff at a three-story facility next door were rescued uninjured after evacuating to the top floor, said Iwate prefectural official Reiko Ouchi.

A caretaker at that facility notified the town office about their evacuation to the third floor, noting that the nine residents next door were stuck, NHK TV reported.

Ouchi said officials are looking into if and how town officials responded to the call. An evacuation order was not issued.

Hiroaki Sato, a senior official at the company that runs the nursing homes, said floodwater poured into the compound in a matter of 10 minutes, making it impossible for the nine elderly residents to escape. The water was at chest-high Tuesday evening.

Despite earlier warnings of the approaching typhoon, only one of the eight staff was on overnight duty, Sato told Kyodo News, adding that a telephone line was cut off due to flooding and she could not reach police or firefighters.

"An overnight staff attended the residents, but in the end they all died, including one in (her) arms," Sato told nationally televised NHK news. "I'm so sorry we could not help any of the nine residents," he said, as he bowed deeply in apology, his teary voice trembling.

The identity of the victims and other details, including the whereabouts of their caretakers, were not immediately known, said Takehiro Hayashijiri, a prefecture disaster management division.

Authorities found two more bodies in Iwate — one in the same town and the second in another town of Kuji, according to the Fire and Disaster Management Agency.

Footage on NHK showed the nursing home partially buried in mud, surrounded by debris apparently washed down in the swollen river. A car by the home was turned upside down.

At another nursing home, a rescue helicopter was perched atop a flat roof, airlifting residents, each wrapped in a blanket and carried by their helpers.

"We're making a government-wide effort to assess the extent of damage," Chief Cabinet Secretary Yoshihide Suga told reporters. The government sent troops to help in the rescue and cleanup effort.

Farther north, on the island of Hokkaido, at least two rivers broke through their banks. The disaster management agency said at least one person went missing in a car that went down with a bridge torn away by the flood.

Authorities in the town of Minamifurano reported hundreds of people trapped in houses and shelters by flooding from the Sorachi river, the agency said. Hundreds of others were also trapped in buildings and isolated in several towns in Iwate.

Typhoon Lionrock made landfall Tuesday evening near the city of Ofunato, 500 kilometers (310 miles) northeast of Tokyo on the Pacific coast and crossed the main island of Honshu before heading out to the Sea of Japan.

It was the first time a typhoon has made landfall in the northern region since 1951, when the Japan Meteorological Agency started keeping records.

The scene of large parts of northern Japan covered with muddy water was a shocking reminder of the major tsunami that struck the same region five years ago.

Iwate prefecture, the hardest-hit by the typhoon, is one of the areas still rebuilding from the March 2011 tsunami and earthquake, which left more than 18,000 people dead along Japan's northeastern coast.